Boron vs Fermium

PropertyB BoronFm Fermium
Atomic number5100
SymbolBFm
NameBoronFermium
Categorymetalloidactinide
Standard Atomic Weight10.8135 u257 u
Period27
Group13N/A
Blockps
Phase at STPsolidsolid
Electron configuration[He]2s22p1[Rn] 5f12 7s2
Oxidation states[-5, -1, 0, 1, 2, 3][2, 3]
Electronegativity (Pauling)2.041.3
Electron affinity0.27972 eV0.339 eV
Density2370 kg/m³9700 kg/m³
Melting point2074.85 °C1526.85 °C
Boiling point3999.85 °C-273.15 °C
Discovery year18081952